<!doctype html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>js示例4-10-21</title>
	<script>
		var arrayA = [13,16,234,43,8,90];
		var B=arrayA.push(489);
		alert(B);
		alert(arrayA);
		
	</script>
</head>
<body>
	
</body>
</html>